Redox-Neutral Photocatalytic Germylative Difunctionalization of Unactivated Olefins via Selective Radical Capture by Ge(II)

This study reports the development of a photocatalytic germanyl functionalization of unactivated olefins. A modular approach to alkylgermanium trihalides was realized through a three-component radical reaction involving fluoroalkyl bromides and commercially available GeBr2 in a redox-neutral process. The target organogermanes were readily obtained via one-pot derivatization using various Grignard reagents, demonstrating good functional group compatibility with amides, esters and ketones. This work highlights the utility of Ge(II) reagents in constructing C–Ge bonds via photoredox catalysis. Notably, the selectivity in capturing electrophilic or nucleophilic radicals by Ge(II) was found to be significantly influenced by the halide ligands on GeX2.